(a) Field of the Invention
The present invention relates to a white light light-emitting device, and more particularly to a light-emitting device that is able to emit white light having superior color rendering and that is more uniform.
(b) Description of the Prior Art
With reference to Taiwan publication No. 383508, entitled Light-emitting Device, Taiwan publication No. 385063, entitled White Light LED, Taiwan publication No. 556365, entitled Method of Manufacturing White Light Light-emitting Diode Light Source, and Taiwan publication No. 465123, entitled High Power White Light-emitting Diode, the aforementioned light emitting devices all utilize inorganic polymer components (such as YAG (yttrium aluminum garnet) yellow phosphor layer. However, because when a phosphor layer is coated on a surface and a periphery of a light-emitting member (LED light-emitting diode), uniformity of the phosphor layer and adhesion is unable to be effectively controlled, thus excited mixed light (white light) becomes mutually intermixed and non-uniform, for instance, the white light may have a blue bias at a center and a yellow bias at a periphery. Although the naked eye might see white light, however, when the mixed light is projected onto pure white paper, then a central blue color and a yellow bias around the periphery is apparent.
Hence, subject of the present invention is resolving and surmounting existent technical difficulties to invent a light-emitting device that is capable of emitting white light having superior color and better uniformity.